SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7141652ae3d50088e4b30bd21b4059ba6b1d5f7798835c5f28204f9d8cf5a7bf' 
  AND token = 'OUXMKWgKLkFzH3Yu5fSQ2PzDbaWYY0l/oCIPm6hS4Jg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}